FFmpeg/libavformat/ncdec.c
Stefano Sabatini 72415b2adb Define AVMediaType enum, and use it instead of enum CodecType, which
is deprecated and will be dropped at the next major bump.

Originally committed as revision 22735 to svn://svn.ffmpeg.org/ffmpeg/trunk
2010-03-30 23:30:55 +00:00

102 lines
2.5 KiB
C

/*
* NC camera feed demuxer
* Copyright (c) 2009 Nicolas Martin (martinic at iro dot umontreal dot ca)
* Edouard Auvinet
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "libavutil/intreadwrite.h"
#include "avformat.h"
#define NC_VIDEO_FLAG 0x1A5
static int nc_probe(AVProbeData *probe_packet)
{
int size;
if (AV_RB32(probe_packet->buf) != NC_VIDEO_FLAG)
return 0;
size = AV_RL16(probe_packet->buf + 5);
if (size + 20 > probe_packet->buf_size)
return AVPROBE_SCORE_MAX/4;
if (AV_RB32(probe_packet->buf+16+size) == NC_VIDEO_FLAG)
return AVPROBE_SCORE_MAX;
return 0;
}
static int nc_read_header(AVFormatContext *s, AVFormatParameters *ap)
{
AVStream *st = av_new_stream(s, 0);
if (!st)
return AVERROR(ENOMEM);
st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
st->codec->codec_id = CODEC_ID_MPEG4;
st->need_parsing = AVSTREAM_PARSE_FULL;
av_set_pts_info(st, 64, 1, 100);
return 0;
}
static int nc_read_packet(AVFormatContext *s, AVPacket *pkt)
{
int size;
int ret;
uint32_t state=-1;
while (state != NC_VIDEO_FLAG) {
if (url_feof(s->pb))
return AVERROR(EIO);
state = (state<<8) + get_byte(s->pb);
}
get_byte(s->pb);
size = get_le16(s->pb);
url_fskip(s->pb, 9);
if (size == 0) {
av_log(s, AV_LOG_DEBUG, "Next packet size is zero\n");
return AVERROR(EAGAIN);
}
ret = av_get_packet(s->pb, pkt, size);
if (ret != size) {
if (ret > 0) av_free_packet(pkt);
return AVERROR(EIO);
}
pkt->stream_index = 0;
return size;
}
AVInputFormat nc_demuxer = {
"nc",
NULL_IF_CONFIG_SMALL("NC camera feed format"),
0,
nc_probe,
nc_read_header,
nc_read_packet,
.extensions = "v",
};